The point of this thread is to post useful SEO tools or websites that you come across. Please post them as you find them and I will just add them to my post here so we have one nice list of SEO tools. I will start......

linksphinx.com - Link Sphinx - a free backlink checker software for PC

Link Centaur - a fresh backlink indexing service. There is a free plan: 50 URLs per day.

The point of this thread is to post useful SEO tools or websites that you come across. Please post them as you find them and I will just add them to my post here so we have one nice list of SEO tools. I will start......

You can try our (owners of this forum) site and link audit tool: A1 Website Analyzer
http://www.microsystools.com/products/website-analyzer/

After doing a website crawl, it can filter and show you all pages (including broken links to internal and external URLs), file sizes, response codes, duplicate content, titles, descriptions, H1, H2 canonical, internal anchor text to pages, link line numbers, link follow/nofollow states, all top keywords, calculate internal link juice "score" of all pages, validate HTML/CSS, spell check and perform custom search for text/patterns throughout and more

For a full run-through and guide of all the features and uses, see:
http://www.microsystools.com/products/website-analyzer/help/site-analysis-seo-audit/